Method of producing a foot orthotic through 3d printing using foot pressure measurements and material hardness and/or structure to unload foot pressure

ABSTRACT

A method and apparatus for generating a custom made orthotic or insole for footwear. Information relating to the pressure applied by the sole of a person&#39;s foot is used to custom produce an orthotic or insole for the person by using softer material or different structural components, selectively located at pressure points of a particular individual, to unload pressure on the foot at those points. Pressure readings taken for the foot of an individual identify pressure points for that foot. The pressure points are quantified and the foot is “mapped” in a grid format on a pressure map. Once mapped, structural components corresponding to a particular pressure value are positioned in the orthotic based on the mapping. The compression cells are created via 3D printing methods based on an individual&#39;s pressure readings and results from an electronic pressure plate utilizing pressure response sensors.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on, and claims priority to, U.S. ProvisionalApplication No. 62/458,946, filed on Feb. 14, 2017, the entire contentsof which being fully incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to pedorthics for preventing and relievingfoot problems and has particular applicability to orthotics custom madefor an individual.

Description of the Related Art

Foot problems and the corresponding costs associated with foot care costmillions of dollars. In cases where the foot problem is debilitating forparticular activities, a number of hours of work time can be lost. Footproblems can arise from medical conditions, work conditions requiringstanding or walking, athletic activities, and the like. Thus, footproblems can develop from medical conditions, work activity or leisureactivity.

Pedorthics is the art concerned with the design, manufacture, fit, andmodification of footwear, foot orthotics, and foot appliances asprescribed to help relieve painful or disabling conditions of the foot.For those who practice any level of pedorthics, the goal is to provideprotection and comfort to the consumer/patient. One of the primary waysof achieving this has been to reduce pressure at the greatest areas ofimpact. This has historically been accomplished with orthotics and/orexternal modifications to footwear.

One conventional method for providing protection and comfort to aconsumer or patient is to use orthotics or insoles inserted intofootwear to cushion the sole of the foot. There have also been productsthat reduce pressure by modifying a removable orthotic or insole thatfits inside a shoe by removing selected pieces of the orthotic orinsole.

There are generally two ways that orthotics are made in the prior art.In a first method, a cast of the foot is made to essentially provide a“template” for the eventual orthotic. According to this method, a hardthermoplastic material often is heated to soften it and then thesoftened thermoplastic material is molded to the cast of the foot sothat the thermoplastic material takes the shape of the mold (and thus ofthe foot), and then it is cooled so that it becomes hard again. In asecond method a mold is created from the cast of the foot and well-knowninjection molding techniques are used, typically whereby heatedthermoplastic or thermosetting polymers are forced into the mold cavitywhere it cools and hardens to the configuration of the cavity.

More recently, 3D printing technology has been used essentially tocustom produce the orthotics or insoles without the need to go throughthe processing steps described above to create the mold, heat thethermoplastic material, and then form it on or inject it into the mold.Instead, data defining the shape of the orthotic is input to the 3Dprinter to create the finished product in the same manner that any3D-printed product is made. However, unlike the present invention, theend product in the prior art remains essentially the same as the endproduct created by the process for heat forming thermoplastics describedin the prior art to produce a hard insert shaped to the foot of the userCommonly-assigned U.S. Pat. No. 7,493,230 discloses a method andapparatus for generating an orthotic or insole for footwear usinginformation relating to pressure applied by the sole of a foot, whichinformation is correlated to removable pieces of the orthotic or insole.Embodiments include a method and apparatus for generating an orthotic orinsole for footwear, including receiving data from a pressure platecorresponding to a pressure map of the sole of a foot; determiningregions of high relative pressure exceeding a predetermined relativepressure level within the pressure map; and associating data related tothe regions of high relative pressure to an orthotic or insole includingremovable orthotic or insole pieces corresponding to the pressure map.In some embodiments a report is generated of the associated data relatedto the regions of high relative pressure. In a further embodiment thereport provides information relating to the removable pieces of theorthotic or insole associated with the regions of high relativepressure.

While the above-described products and methods result in a reduced footpressure, it would be desirable to have a method and system by which3D-printing technology could be used to extract pressure informationfrom the pressure map of the prior art and selectively vary thestructure and/or material hardness at selected areas of a custom madeorthotic or insole to custom make orthotic shoes or orthotics or insolesfor individuals.

SUMMARY OF THE INVENTION

An advantage of the present invention is a method and apparatus forgenerating a custom made orthotic or insole for footwear. The inventivemethod and apparatus use information relating to the pressure applied bythe sole of a person's foot to custom produce an orthotic or insole forthe person by using different structural components, selectively locatedat pressure points of a particular individual, to unload pressure on thefoot at those points. In a basic configuration the structural componentscan comprise, for example, individual compression cells having agenerally-compressible lattice structure, that is, having an interlacedstructure of compressible material configured in a regular repeatedthree-dimensional arrangement, as illustrated more fully in theaccompanying drawings. Pressure readings taken for the foot of anindividual identify pressure points for that foot. In a preferredembodiment the pressure points are quantified and the foot is “mapped”in a grid format on a pressure map. Once mapped, structural componentscorresponding to a particular pressure value are positioned in theorthotic based on the mapping. In a preferred embodiment the compressioncells are created via 3D printing methods based on an individual'spressure readings and results from an electronic pressure plateutilizing pressure response sensors. A goal of invention is to unloadfoot pressure in high pressure areas of the foot by adjusting theorthotic material hardness, softness, and/or structure of the orthotic.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a basic block diagram of a system according to the presentinvention; and

FIG. 2 is a flowchart showing the basic steps of the present invention;

FIG. 3 illustrates a bottom view of an orthotic or insole insert createdaccording to a method of the present invention;

FIG. 4 illustrates a left view of an orthotic or insole insert createdaccording to a method of the present invention;

FIG. 5 illustrates a right view of an orthotic or insole insert createdaccording to a method of the present invention;

FIG. 6 illustrates a top perspective view of an orthotic or insoleinsert created according to a method of the present invention;

FIG. 7 illustrates the structure of compression cell in greater detail,where thirteen compression cells adjacent to each other, correspondinggenerally to the thirteen-cell configuration shown, for example, at theheel portion of FIG. 3;

FIG. 8 illustrates a single compression cell;

FIGS. 9 and 10 illustrate the structure of compression cell in greaterdetail;

FIG. 11 illustrates twenty-nine individual compression cells;

FIG. 12 illustrates a single compression cell;

FIG. 13 illustrates an interior structure 1204 of the compression cell310 shown in FIG. 12; and

FIGS. 14 to 20 illustrate, without limitation, additional examples ofconfigurations for compression cells that can be used and which arecovered by the appended claims.

DETAILED DESCRIPTION

The concept underlying the invention is to manufacture a custom footorthotic or insole through 3D printing based upon pressure measurementsof an individual's foot. In a preferred embodiment the pressuremeasurements are mapped to create a data model of the foot after theindividual stands upon an electronic pressure plate that uses pressuresensors and receives a pressure analysis of the foot. The data model isthen input to the 3D printer to create a custom orthotic or insole thatprovides differing amounts of pressure unloading appropriate to thefoot, by selectively locating individual compression cells within theorthotic or insole, with the specific compression cell used at aspecific location being selected based on its pressure-unloadingcapability. Through material structure, material hardness, materialsoftness, or a combination thereof, an orthotic or insole is producedthat unloads and helps alleviate high pressure at various locations onthe foot where indicated. The invention is not limited to the use ofsensor devices to take pressure measurements. That is, any manner ofobtaining pressure measurements, including but not limited to, thermalpressure measurement devices, or manual methods such as a Harris matfoot imprinter (e.g., methods where data is obtained and manually inputto the system) can be used to obtain the pressure measurements and stillfall within the scope of the claimed invention.

Polychromatic foot pressure data of the individual being scanned iscollected by the foot scanner. Utilizing the pressure-point analysisreadings from the electronic pressure plate measurements, readings fromeach sensor determine the hardness of various areas on the orthotic orinsole. Softer areas of the orthotic or insole unload pressure in thosespots to the harder areas of the orthotic or insole. The inventionquantifies the varying and gradient foot pressures of the specific footin issue by assigning and allocating numeric pressure values within adesignated numeric range to each pressure reading (by way of example andnot limitation, the range can be from 1 to 15 with 1 being lowestpressure and 15 being the highest pressure). Certain areas of the footorthotic or insole can utilize either harder and/or softer materials toaccommodate for various pressure readings of the individual's foot. Theorthotic material can be softer in locations where foot pressuremeasurements read higher to help unload and alleviate excessive pressureand transfer pressure to other areas.

Alternatively (or in addition to varying the hardness or softness of thematerials), certain areas of the foot orthotic or insole can utilizestructural adjustments (e.g. the yielding capabilities, yieldingparameters, weave process) to cause the structure to react differentlyto different pressures to accommodate for higher or lower pressurereadings of an individual's foot.

The invention may utilize material softness, hardness, and/or materialstructure either individually or in any combination thereof to producethe orthotic or insole. Each pressure reading from the sensors isassociated with a different structure, hardness, or combination thereofmaking the production of the orthotic or insole directly coordinatedwith the foot pressure analysis results. The invention converts the CAD(computer-aided design) model of an orthotic or insole into a grid whichmay vary in size (by way of example and not limitation, 1 cm×1 cm grid;¼ cm×1 cm grid; etc.), where each individual grid file corresponds to apressure sensor. From that matrix, an individual structure at a gridlocation, or a designated number of different groupings of structures,can be created based on the scan data in issue (by way of example andnot limitation, there could be a single individual structure at aparticular grid location, or 3 different groupings, 6 differentgroupings, 10 different groupings—the more groupings there are, thehigher the “resolution” of the orthotic, and any number of groupings,smaller (including a single structure at a single grid location) orlarger, can be utilized). Each point on the grid is assigned a pressurenumber and a structure, or grouping(s) of structures are placed at thegrid locations accordingly. After assigning pressure map data to theindividual models within the grid/matrix, the individual models are thenidentified by pressure number and the designated number (e.g., 6, 7, 8,. . . n) of consolidated models are created. The designated number ofpressure models (e.g., 6) are then assigned specifically engineered scanstrategies and internal support structures to create pressure responsemodels of orthotics.

A preferred method of delivering usable foot pressure analysis data fromthe electronic pressure plates to the 3D printer is viastereolithography (STL) process. Stereolithographic models have beenused in medicine since the 1990s, for creating accurate 3D models ofvarious anatomical regions of a patient, based on datasets from computerscans. An exemplary conventional pressure plate device for use inpracticing the present invention is the iStep® Pressure Plate, availablefrom Aetrex Worldwide, Inc. of Teaneck, N.J. The iStep® system for usewith this pressure plate is a digital pressure analysis system thataccurately takes a pressure reading of a person's feet. The technologyuses pressure sensors that are 0.25 cm², and properly identifies whichareas of a person's feet absorb the most pressure and/or impact whilestanding.

When using the pressure plate, a person stands on the pressure plate for10 to 30 seconds or some other suitable amount of time, and the sensorstransmit signals to a computer to map out, and illustrate, the foot. TheiStep® pressure plate has over 3700 sensors, but typically only abouthalf end up in contact with the feet. In most cases, each footencounters between 800-1200 sensors, and the technology gives a readingfor each sensor based on the force that is placed on the sensor, forminga “pressure map” of the foot. Similar to a fingerprint, this reading isindividualized, and there are typically differences in pressuredisbursement from one person to the next.

According to a preferred embodiment of the present invention a foot isscanned using pressure sensors and then the scan-data is processed usingstereolithography and a processor configured to translate the data intoinput to a 3D printer that produces a custom orthotic or insole thatreduces excessive foot pressure in areas where needed based upon anindividual's pressure measurements, as described in more detail below.Systems and methods described for obtaining the foot pressure analysisdata and its mapping to a particular foot are described in U.S. Pat. No.7,493,230, incorporated fully herein by reference.

Under the preferred STL method, the file format will permit 3D shapes tobe readable by 3D printer software and hardware. The transfer format mayrequire programming adjustment and/or editing, including but not limitedto manual adjustments and/or editing, depending upon the specific 3Dprinter in use and the printers' methods of communication between thesoftware components in use; i.e., the 3D printer's applicationprogramming interface (API) that it provides and which may include itssubroutine definitions, protocols, and other tools for adjusting and/orcreating the application software.

Alternative formats of data transfer may be used including withoutlimitation, manual data transfer.

FIG. 1 is a basic system diagram showing a system of the presentinvention. As can be seen if FIG. 1, a pressure sensor 10 for takingfoot pressure measurements, such a as an electronic pressure platesensor (e.g., an AETREX iStep NOVA foot scanner) is coupled to aprocessor 12 that is, according to the present invention, configuredwith code that will cause the processor to perform stereolithography onthe data output from the pressure sensor 10, and output 3D printer datathat will configure a 3D printer 14 to create a custom orthoticcorresponding to the foot pressure measurements taken by the pressuresensor 10.

FIG. 2 is a flowchart describing the steps performed by the system ofFIG. 1 to create the custom orthotic or insole. At step 20, a foot isplaced on the pressure sensor and it takes pressure readingcorresponding to the foot, and outputs the pressure data to theprocessor. At step 22 the processor receives the pressure data and usesa stereolithography process to transform the pressure data to 3D printerdata that will instruct a 3D printer how to create the custom orthoticor insole. At step 24, the 3D printer data is received by the 3Dprinter, and creates a custom orthotic based on the 3D printer data. AtStep 26 the process ends.

Referring now to FIGS. 3-20, an orthotic or insole and method ofproducing same according the present invention, are described. FIGS. 3-6illustrate a bottom view, left view, right view, and top perspectiveview of an orthotic or insole insert created according to a method ofthe present invention. In FIG. 1, for example, it can be seen that theentire orthotic or insole insert is created of different types ofcompression cell structures 302, 304, 306, 308, 310, 312, 314, 316, 318,and 320. In accordance with the present invention, each compression celltype is created with a different structure, with each structuredictating the pressure response for each compression cell. For example,as discussed further below in more detail, compression cell type 302utilizes larger, more flexible elements in its structure, making itmore-easily compressed and thus giving it a greater pressure responseand making it have a softer “feel” when placed underfoot. By way ofcontrast, compression cell type 310 utilizes a smaller, more solid andmore compact structure, making it less-easily compressed and thus givingit a lesser pressure response and making it have a harder “feel” whenplaced underfoot. Each of the compression cell structures 302, 304, 306,308, 310, 312, 314, 316, 318, and 320 differ in some manner such that,in this example, ten different pressure responses can be assigned to thevarious locations on the grid of the orthotic to enable very precise andhigh-resolution pressure response throughout the surface of the orthoticor insole. It is understood that these ten compression cell structuresare provided for purpose of example only and that a person of ordinaryskill in the art, given the information contained herein, could developmany other alternative compression cell structures that provide aparticular desired pressure response, and all such alternatives andmodifications fall within the scope of the invention claimed herein.

FIGS. 7 and 8 illustrate the structure of compression cell 302 ingreater detail. FIG. 7 illustrates thirteen compression cells 302adjacent to each other, corresponding generally to the thirteen-cellconfiguration shown, for example, at the heel portion of FIG. 3. FIG. 8illustrates a single compression cell 302. As can be seen in theFigures, each compression cell 302 comprises a generally circular topportion 802, a generally circular bottom portion 804, and, in thisexample, four generally helical or spiral flex elements 806 connectingcircular top portion 802 and circular bottom portion 804, as shown. Thematerial used to create compression cells 302 is, in a preferredembodiment, a resilient material that can flex, but will not break, whencompressed. Examples of such material include (but are not limited to)TPU (thermoplastic polyurethanes), Nylon, and TPE (thermoplasticelastomers.

As can be understood from the above-description and the drawings, whenforce is applied downward onto top portion 802, the helical elements 806deform in a downward direction, allowing top portion 802 to movedownward, providing a “spongy” feel underfoot. Because the material isresilient, when downward the pressure on top portion 802 is reduced, thehelical elements 806 bias back towards their at-rest position, thus alsomoving top portion 802 back upwards towards its at-rest position.

FIGS. 9 and 10 illustrate the structure of compression cell 306 ingreater detail. As best shown in FIG. 9, each compression cell 306comprises a grouping of four smaller versions of compression cell 302,joined together to form an essentially square cell, the details of whichare best described in connection with FIG. 10. In this example, eachcompression cell 306 takes up approximately the same “footprint” as eachcompression cell 302; in other words, four smaller versions ofcompression cell 302 are joined together to form a single compressioncell 306 which takes up essentially the same amount of space ascompression cell 302. In a preferred embodiment the resilient materialused for compression cell 302 is also used for compression cell 306 (andin fact, for all of the compression cells) so that, rather than havingto use a different material with a different level of resilience, thepressure response is varied based on the structure used rather than thematerial used. This simplifies the 3D printing process, because therewill be no need to vary the material used for the 3D printing.

It will be understood by one of ordinary skill in the art that by using,in compression cell 306, a greater amount of resilient material and agreater structural density than that of compression cell 302,compression cell 306 will be less-easily compressed and thus have alesser pressure response than compression cell 302.

FIGS. 11-13 illustrate the structure of compression cell 310 in greaterdetail. FIG. 11 illustrates twenty-nine individual compression cells310; FIG. 12 illustrates a single compression cell 310, and FIG. 13illustrates an interior structure 1204 of the compression cell 310 shownin FIG. 12. As shown in FIG. 12, compression cell 310 comprises anexternal “web-like” structure 1202 connected to and surrounding apolyhedron-shaped interior structure 1204. As can best be seen in FIG.13, polyhedron-shaped interior structure 1204 is a relatively densestructure that will take more downward pressure to compress thancompression cells 302 or 306, and when coupled to and surrounded by theexternal web-like structure 1202 as shown in FIG. 12, is even lesscompressible. Compression cell 310 also takes up the same footprint as asingle compression cell 302 or 306.

FIGS. 14-20 illustrate, without limitation, additional examples ofconfigurations for compression cells that can be used and which arecovered by the appended claims. As is known in the art, 3D printers canbe supplied with instructions to create elements of virtually any shapethat can be modeled and input to the printer; the compression cellsdescribed in detail above and shown in the drawing figures are providedas examples only and the claims herein are intended to cover not onlythe illustrated and described configurations, but compression cells ofany configuration that can provide varying degrees of pressure responsebased on their structure and composition.

It is also understood that materials of different resilience can be usedselectively throughout an orthotic, i.e., the materials need not be thesame materials for each compression cell, although it provides for asimpler construction if the 3D printer uses a single material for all ofthe compression cells.

Any software steps described herein can be implemented using standardwell-known programming techniques. The novelty of the above-describedembodiment lies not in the specific programming techniques but in theuse of the steps described and the various structures, materials,hardness/softness of materials, etc. disclosed to achieve the describedresults. Software programming code which embodies the present inventionis typically stored in permanent storage. In a client/serverenvironment, such software programming code may be stored with storageassociated with a server. The software programming code may be embodiedon any of a variety of known media for use with a data processingsystem, such as a USB drive, DVD, jump drive, or hard drive. The codemay be distributed on such media, or may be distributed to users fromthe memory or storage of one computer system over a network of some typeto other computer systems for use by users of such other systems. Thetechniques and methods for embodying software program code on physicalmedia and/or distributing software code via networks are well known andwill not be further discussed herein.

It will be understood that each element of the illustrations, andcombinations of elements in the illustrations, can be implemented bygeneral and/or special purpose hardware-based systems that perform thespecified functions or steps, or by combinations of general and/orspecial-purpose hardware and computer instructions.

These program instructions may be provided to a processor to produce amachine, such that the instructions that execute on the processor createmeans for implementing the functions specified in the illustrations. Thecomputer program instructions may be executed by a processor to cause aseries of operational steps to be performed by the processor to producea computer-implemented process such that the instructions that executeon the processor provide steps for implementing the functions specifiedin the illustrations. Accordingly, FIGS. 1-2 support combinations ofmeans for performing the specified functions, combinations of steps forperforming the specified functions, and program instruction means forperforming the specified functions.

While there has been described herein the principles of the invention,it is to be understood by those skilled in the art that this descriptionis made only by way of example and not as a limitation to the scope ofthe invention. Accordingly, it is intended by the appended claims, tocover all modifications of the invention which fall within the truespirit and scope of the invention.

1. A method for 3D-printing an orthotic or insole, comprising: gatheringpressure-point data or information of a foot using a pressure-analysisdevice; inputting the gathered pressure-point data or information to a3D printing device; and configuring the 3D printing device to print theorthotic or insole such that locations of the orthotic or insolecorrelated to pressure-point data or information of the foot indicativeof a higher pressure level have a softer feel underfoot than otherlocations of the orthotic or insole.
 2. The method of claim 1, whereinthe locations of the orthotic or insole correlated to pressure-pointdata or information of the foot indicative of a higher pressure levelare printed using softer material than the material used in the otherlocations of the orthotic or insole.
 3. The method of claim 1, whereinthe locations of the orthotic or insole correlated to pressure-pointdata or information of the foot indicative of a higher pressure levelare printed using a structure that renders them softer underfoot than astructure used in the other locations of the orthotic or insole.
 4. Amethod for custom making an orthotic or insole for footwear, the methodcomprising: receiving data obtained from a pressure detector, said datacorresponding to a two-dimensional pressure map identifyingpressure-point locations of the sole of a foot; determining a pressurenumber for each identified pressure-point location within said pressuremap; creating, for each different pressure number, a compression cellcorresponding to each different pressure number; and forming saidorthotic or insole by placing in the orthotic or insole a compressioncell corresponding to the pressure number corresponding to eachidentified pressure-point location on the pressure map.
 5. The method ofclaim 4, wherein said creating and forming steps are effected by a3D-printer receiving data identifying the pressure number for eachidentified pressure-point location within said pressure map.
 6. Themethod of claim 5, wherein the pressure number corresponding to aparticular compression cell is determined by a physical structure usedto create the particular compression cell.
 7. The method of claim 5,wherein the pressure number corresponding to a particular compressioncell is determined by a softness of material used to create theparticular compression cell.
 8. The method of claim 6, wherein thelocations within the pressure map are defined by a grid havingequally-sized grid locations.
 9. The method of claim 8, wherein eachcompression cell is of the same size as each grid location.
 10. Themethod of claim 8, wherein each compression cell is larger than the sizeof each grid location.
 11. The method of claim 8, wherein eachcompression cell is smaller than the size of each grid location.
 12. Themethod of claim 8, wherein multiple compression cells are combined tocreate a compression cell grouping.
 13. The method of claim 12, whereinthe orthotic or insole comprises multiple compression cell groupings.14. The method of claim 13, wherein different compression cell groupingscomprise a different physical structure.
 15. A device for creating acustom orthotic or insole, comprising: a foot pressure sensor sensingpressure-points of a foot placed thereon and providing datacorresponding to said sensed pressure-points; a processor coupled tosaid foot pressure sensor and configured to receive the provided datacorresponding to said sensed pressure-points and performstereolithography on said output data corresponding to said sensedpressure-points, to create 3D printer input data; and a 3D printercoupled to receive said 3D printer input data and configured totransform said 3D printer input data to a custom orthotic or insolecorresponding to said pressure-points of said foot.